Circuit arrangement for wireless transmitters.



E. VON LEPEL.

CIRCUIT ARRANGEMENT FOR WIRELESS TRANSMITTERS.

APPUCATION FILED FEB. 1|. 1914.

1 04,720. Patented Nov. 14, 1916 W ,L -i wz/ wm nvww 4' 12 p form STA'EEfi Y sa-sizes van LEPEL. or snummwrnmnnsnonr, GEBIANY. I

omouz'r xmnononmsn'r on wmmsss TRANSMITTERS specification of Letters istent. Patefited Nov, 1-1, 1916,

Applicatiuufllediebruary11,1814. SariaINoBlSilQ'f nj'll nil u'fiu'm it wlfil/ canon-u r 1 Be it known that I. Euisnlrr \ON LEPBL,

a subject of thoKing of Prussia, residingat' lli-rlin-ll'il'znersdorf, in the Empire. of

5 Germany. have invented new and useful In provrzncnts in Circuit Arrangements for \l'irelcss 'lrmisnnitters. of which the :tollowing is u spcclhcation. 0.

My invention relates to u novel method of 19 producing n low frrqueney current in a sim ple and effective manner from a' high-frequency current so an; to render the latter prrcoivuhlc in telephonic receivers.

In the accompanying drawing, Figure 1 is n iliuirrnm illustrating one of the prior methods: for producing lo\\'frcqltel\cy cnr-' root from high-frequency ('l1lI'Elll3;'-Flg.2 a diagram illustrating my nor-cl method for producing Iomfrequcncv current from. high- 20 froqueuor current, and Fig. 3 n diagram showing it modification of Fig. 2.

The oscillations produced from continuous rurrr-nt by means of n generator of high frequency const'rnctml according to loulscn. \on Lope]. and others, .ure, as is well known. entirely, or nearly entirely, continuous so that they nre not opt to be received. without artificial menus, in u detecting device of u telephonic receiver. An interrupter or :1 similar arrangement will have to he provided for in the receiver or in the transmitter. A; very simple solntionfor the latter case was proposril by von Lope] dud Burstyn in the your 1008. This is the so called continnous-current tone transmitter which is so constructed that in; addition to thohigh frequency circuit 2 c which includes the generator g (Fig. 1) for high frequency oscillations fed from the line 1 p,another parallcl circuit of low frequency is established that comprises the ports 9 t a; 'Enchiiof the two ci rcn i tsfu rnishe's by discharging through the oscillation generator-an altemoting current of its speiaificr-periodicity; When both 4t circuits are connected with l the iqcillation goo one obtains the resnlt'thntthe intensity ,of the high frequency oscillations v of tho cirouit's o pillsatesrin the rhythm ofitho (Boil-l lotions oistho low frequencv circuit t-ol. This latter -eireuit is generally tuned to a readily perceivnble tone frequencmthot 1a to some number pfwibrations, for instance 1000 per ssoonri, whioh the human our will peroeiveas' sonncl. The present invention j as differs from this scheme by the f wghao the lowfz cquenoy oiieuit is not-connected in firs is wanted for the circuit 0 parallel with the oscillation enerutorfand that it min in consequence not a excited for itself. T his circuit in this case is shunted 10 a part oftlie capacity of the high frequcncy circuit, For this purpose tho battery of comlcuserof this circuit c'onsi'sts of "at least two condensers or two groupspof'con- ATENT OFFICE.

dens-tors connected in series (0 and dfinFi 2); to one or to one 'group ofthosela) n coll f is connected in pgrnllel. This arrange mcnt hns the result that the high frequency oscillations of the circuitc d a (say 1,000,000 oscillations per second) ore decomposed'in groups ofjone frequency such thnt'thejnb come singing oscillations. Tho pitch' of the note depends on the self-incluctibnbf"the coil f on the one hand :uulof th'e" resultihg capacity of the two condensers on the other hand and may-"ho altered by.menns :of'one of these electrical factors by. means of a keyhonrilfor instance. i

The advantage of'this-new methodcoo sists in the fact that no special-condenser tone frequency.

'lheieforothc 'npparatus becomes simpler and cheaper.

Fig. 3 shows a scheme of connecti'ons in which a condenser cis put in series the coil t, but this alteration is of 'no greabim-f portancc.

If Ynstcad of a continuous current-an spark-gap or on are.

thetone frequency circuit is tuned-to the pitch fifths-alternator. 4 v i 'For tgonsmittingwireless 'key I: may boplaeed inthifediii current ineor in the circuit of the low Gilli-[8011M in the drawing. "What 1 claim is: l 1 v .1. In a wireless-transmitter," p moin osoil ating current of tone ire uency to iiquonching l.

n aqchn case-the newi V scheme may V serve to obtain batten-l. ton'ps if lotion circuit of high frequency including: a

condenser and. a coil in series, snd gn iuxil 1' i513; ossification circuit arranged in) shtint W oh bridges a portion of'ihg ca-5 l0 iliary circuit having a lation circuit of hi h frequency including a condenser and a col l in series, and an auxiliary oscillation circuit arranged in a shunt which bridges a portion of the condenser capacity of said main circuit, and includes a coil, said auxiliary circuit having :1 lowfrcqucncy period of oscillation such as c0r rvsponds to sounds audible to the human ear.

EGBERT vox LEVEL.

Witnesses WAnmnmR HAuP'r, HENRY Menu. 

